The ecological effects of invasive ants on ecosystems will depend largely on ant abundance. Cypress savannas of the southeastern United States have high conservation worth, supporting diverse and rare assemblages of species. Distance sampling was used to determine the abundance and distribution of colonies of the invasive ant, Solenopsis invicta Buren, in cypress savannas of two Carolina bays. Colonies were distributed throughout the savannas, save for areas of dense tree or shrub cover. Colony densities were much less than those reported for disturbed habitats and were similar between bays. Free-standing mounds were more common in the historically less flooded bay, and they had significantly greater volume and colony biomass as compared with these mounds in the other bay. Unlike previous studies, reporting only monogyne colonies for intact habitats of the southeast, both monogyne and polygyne colonies were present in the cypress savannas; <60% of the colonies were monogyne. Cypress savannas join a growing list of habitats, having wet sandy or loamy soils and little canopy, that have become invaded by S. invicta in the absence of anthropogenic soil disturbances. Cypress savannas resemble invaded longleaf pine savannas in vegetation physiognomy, history of fire, and dense herbaceous ground cover. While fires are critical for biodiversity, the resulting dense herbaceous ground cover may favor S. invicta. As generalist consumers and likely the most abundant ant species in these habitats, S. invicta could have important direct and indirect effects on the native communities.

The Florida Everglades ecosystem represents a significant wetlands area and serves as a terrestrial carbon reservoir mediated in large part by microorganisms. Shotgun metagenome sequencing provides a snapshot of microbial diversity and the frequency of metabolic and functional gene content. Here, we present an analysis of 20 sediment samples collected from the Arthur R. Marshall Loxahatchee National Wildlife Refuge to characterize the taxonomic and functional potential of the microbial and viral communities, and reconstructed metagenome- assembled genomes. A total of 122 medium-quality and 6 high-quality MAGs are reported, three of which likely represent a novel species within the class Dehalococcoidia. The most abundant phyla of bacteria and archaea were Proteobacteria and Euryarchaeota, respectively. Caudovirales was the most abundant viral order. Significant differences in taxonomic composition and diversity were observed among collection sites. Additionally, water samples were analyzed for pH, total nitrogen, total organic carbon, elements (P, K, Mg, Fe, Mn, Pb, Ca, S), chloride, electric conductivity, orthophosphate, nitrate, and ammonia, while the sediment samples were analyzed for carbon, nitrogen, and pH. Differences in measured aquatic and sediment analytes revealed significant correlations with numerous phyla. Significant correlations were observed between estimated gene frequencies of both aquatic and sediment analytes, most notably between kup/kdpB and dsrA/cysC with potassium and sulfur, respectively, as well as phoD/phnX and cysC with pH. Together, these data provide an important view into the functional and metabolic potential encoded within the sediment microbial communities in the Florida Everglades.